Carburetor



1,625,141 APrll 19 1927 v E. A. NELSON CARBURETOR Filed May 1. 1922 2 Sheets-Sheet'l 1,625.14 Apnl 19, 1921. E A' NELSQN 1 cARBuREToR Filed May 1. 1922 2 sheets-Sheet 2 Summen www Patented Apr. 19, 1927.

Lez-ani niviiL A. NELSON, or HALFWAmMICHIGAN.

CRBURETOR.

Application md May' `1, 1922'. serial Nb. 552608.

aid carburetion, andvthat as the engine speed increases, additional air be introduced to' give" arbetter proportionate mixture of fuel and air for such speeds. Various means have been employed to eifect' control of air to the carburetor but it has been theV common .practice to provide a manually operable cholte and separate automatically operating means forl controlling the admission of air inA accordance withengine speeds, but such arrangements are more or less complicated and are ineflicient due to changes in weather conditions, giving too lean a mixture for fuel powei and speed aty times and too heavy a mixture for efficient andl economical operation at other times.

The object of the present invention is to provide a single manually operable aircon-v trol whereby the proper amount andkindof air may be admitted under all conditions of operation and a dilution" of the ingoing charges effected to give a saving in fuel' consuinption and efficient o aeration. A further object is to simplify car uretor construction and to provide a control which may be at all times conveniently adjusted to suit all weather conditions and engine speeds, and give easy starting and. maximum eiliciency of engine operation with a minimum of fuel consumption.

W ith the above andV other ends in view, the invention consists in providing a carburetor with al single air control member adapted to operate as a choke, and arranged to admit warm air, both warm and atmospheric air infdesired proportions, and to Yopen an auxiliary airsupplyl for effecting admixture of air with t-he carbureted air or combustible charges passing to the engine.

The invention further consists in other matters hereinafter set forth and more particularly pointed out in the appended claims, reference being had to' the accompanying drawings in= which- Figure l is a longitudinal vertical section through-a device illustrative of an embodimentof the invention and showing an Vend portion thereof in side elevation;

Fig. 2' is an end elevation ofthe saine; y

Fig; 3 is a'transverse section substantially upon the line 3-3 of F ig. l;

F igs. 4l and 5 are sections similar toFig. 3, showing a rotary valve member in different operative positions;

Fig. 6 is a longitudinal sectional detail showing the rotary valve in elevation and moved endwise in its casing to open auX- iliaryair inlets;

Fig. 7 is a sectionalA detail of a portion of the casing;

Fig. 8 is a detail of thek rotary Valve 'de` tachedV and partly broken away and in section to disclose its construction; and

Fig. 9 is ay perspective detail of a Venturi member,

'lhe device may be given any desiredgeneral form but as illustrative of a construction suited for use generally in connection with internal combustion engines as einbodied in motor vehicle constructions` a substantially horizontal tubuiarvalve casing l. is provided, said casing being" formed adjaf. cent one end with a lateral extension 2'formand to which a suitable conduit (not shown) may be connected for conducting warmair- The casing l is bored into the carburetor. wardly from one end to receive a.l rotary valve 4' of tubular form having longitudinal slots 5 in its sidewall to register with slotsV toithe casing upon proper rotation of the valve. YThe valve member is also formed with an end wall ll' forming a closure for the open end of the casing bore, said valve projecting from said open .end of the casing a short distance and said projecting end being provided with a pair of latere ing the main airinlet 3 forthe carburetor longitudinal slots ally extending diametrically opposed lugs Y lhaving screw-threaded openings to receive studs or bolts 13 which are provided with locknuts 14 on their outer ends to lock the studs in the positionto which they are adjusted through the openings inthe lugs or ears l2, the opposite or inner ends of-r said vstuds being adapted to engage cam members l5 secured to or otherwise carried by the end et the easing l, said cam members having cam surfaces lll arranged concentric with the axis oi the valve and inclined :in the direction ot' rotation ot the -valve and longitudinally thereof so that a, turning movement ot the 'faire will cause the studs to ride up said inclines and move the valve longitudinally in its bore in the casing. To resist this longitudinal moreincnt oi the yalre and detachahly hold the valve in place within the easing, a ldat spring li" is pirotally secured at one end by a bolt le to a support 'l0 on the end ot the casing lo extend diametrically across the ralve end which valve jnovided with an axial stud 12u haring a reduced outer end to eiigage in oiliening ill in said spring intermediate its ends` the reduced end portion ot the stud torining a shoulder to he engaged by the spring and the reduced end serving to dei'aehably hold the spring in place. The valve rotated by means ot a hand operated rod trl which leads to the dash (not shown) ot the car as other support where it may be conveniently .manipulated by the driver ol the car, and this rod is attached by means ot a universal joint E23 to the outer end ot a laterally extending arm 2l on the projecting end et the valve.

"t tubular extension or continuation 25 ot the valve casing l provides a mixing chainber and an outlet ttor the carburetor, the tree open end 2G ot this tube being adapted to be secured to the uptake pipe ol' an intalie inanitold (not. shown) ot' an engine, the here et this tube being ot less diameter than the bore ot the valve casing so that an internal annular shoulder 2T is formed at the juncture ot the two bores. Fitting within the inner end oi the bore ot the tube Q is a restriction member or bloeit 2S which is 'loi-med with an axial Venturi opening or passage 2S) and through an opening in the lower side ot' this bloeit projects a Vertical nozzle member (see Fig. l) with said nozzle opening into the most restricted part of the lf'enturi passage. :it its lower end. the nozzle 3() opens into a chamber ill termed at the lower lside ot the tube and which chamber is in cominunication with a tloat chamber indicated at 32 in Fig. 2, said lloat chamber containing the usual iloat (not shown) for controlling the height ot fuel therein aud in the nozzle. as is the usual practice in carburetor construct-ions.

)it one end`r the bloeit Q8 is termed with an interrupted llange 33 and a plurality ot external. longitudinally extending channels or groorcs ill are termed in the block, which grooves cut through the flange 33 and torm longitudinal air passages outside the Venturi restriction tor by-passing air past the venturi and nozzle for admixture in the mixing chamber with carbureted air entering said chamber from the venturi. The

usual throttle valve 3G is provided in the mixing chamber ttor controlling the out-tlow ot the mixture et air and tuel through the outlet 26 to the engine.

The end ot the valve Lladjacent the flanged end of the Venturi block 2S, has an end wall 3T termed with a tapered axial opening 38 with the end of the opening ot least diameter adjacentand equal in diameter to the diameter ot the large end ot the Venturi passage .29 in said block, and therei'fore when the valre is in the position shown in Fig. '1, with said end wall in Contact with the end ot the block, said passages 3ft are closed against the passage ot air therethrough, but upon endwise movement oi'f the valve away :trom the venturi, as shown in Fig. G, auxiliary air or air 'for dilution otl the combustible mi;- ture in the mixing chamber will be drawn into the. casing l through the uncovered endsl ot 4he slots (l and Si in the easing wall and will pase` through the several passages Ehlini o the mixing chaniber.

ln order to choke the carburetor tor the purpose ot getting a high suction upon the i'uel nozzle so that tuel chai-ees will he drawn into the engine to facilitate starting7 the valve l is positioned as shown in Figsl and 3, in which position the warm air inlets G and cold air inlets 9 are closed, the valve being in its innermost position with its end wall 3T adjacent the Venturi bloei; with the passages tbl closed thereby. Air is therefore prevented trom passing through these inlets` and all air except a small amount which enf ters due to leakage Will be cutoit from the carburetor and when the engine is turned over in starting, there will be a strong suction upon the fuel nozzle 30 and charges very rich in 'fuel will be introduced into the engine cylinders to effect easy starting, the valve in this position, functioning as the ordinary choke valve usually employed in earburetor construction and operated by a rod running to the dash ot the ear.

As soon as the engine starts, the operator will adjust the valve el to the position shown in Fig. 4t, operating said yalre by means of the rod 22 in the same manner in which he would operate the common 'torni oit carbu rotor choke. The slots or inlets 5 in the valve wall are so positioned and proper tioned relative to the inlets G. that this initial morement will open said inlets G and permit warm air to enter through the main air inlet 3 and pass through the venturi into the mixing chamber, thus giving a comparatively rich mixture `ior maintaining engine operation until the engine warms up and becomes normally operatiif'e.

As soon as the engine becomes warm. the operator will adjust the valve to the position shown in Fig. 5, in which position the inlets (l are still open and the inlets 9 are opened to admit atmospheric air to the venturi and give the proper admixture of air and fuel for normal and lovv speed running.

For high spe-eds and after the engine has become thoroughly warmed up, the operator will give the valve el a further turn, which turning movement Will bring the studs 13 into engagement with the inclines 1G and move the valve endWise, the slots 5 and 8 in the valve Wall being so positioned and proportioned in Width relative to the inlets 5 and 9 in the casing that said inlets Will all remain open during this final operation of the valve which effects an endwise movement thereof to open said inlets beyond the end wall 37 of the valve which has been moved away from the end of the venturi to open the several slots 34, and thus air entering the uncovered end portions ofthe inlets, will be by-passed around the venturi through these slots and admitted to the mixing chamber for the purpose of further diluting the charges.

lVith this arrangement, the admission of all air to the carburetor is under the diret-t manual control of the operator who may conveniently and effectively7 operate the valve io give the proper admiXture of fuel and air under all running and other conditions, illuminating uncertainty and placing carburetor operation directly und-er his immediate and complete control. Further, the present arrangement greatly simplifies and cheapens construction and makes such devices positive and eiiicient in operation.

It Will be understood that the device as shown in the accompanying drawings is merely illustrative ofv an embodiment of the invention and that such changes as fall Within the scope of the appended claims are conten'inlated.

Having thus fully described my invention, what I claim is Y l. A. device of the character described comprising a casing open at its end and formed with air inlet openings adjacent one end, a rotary valve member tting Within and closing one end of said casing, Said valve member being formed with inlet openings to register With the inlets in the casing. a Venturi restriction in the casing, means for supplying fuel to said venturi, said casing` being provided with a by-pass for passing air from one end to the other of the venturi, and means for imparting an end- Wise movement to said valve member to control said by-pass.

2. A device of the character described comprising a casing forming an air passage therethrough and having a Venturi restriction therein with a by-pass for the passage of air past the venturi, said casing being also formed with -a plurality of air inlet openings and an open end, a rotary valve member in the open end of the casing to close the same and to control said inlet openings, means for rotating said valve, a cam for moving said valve longitudinally upon rotation of the valve, said valve being arranged to open said by-pass upon longitudinal movement of the valve, and means for introducing fuel into the Venturi restriction.

3. A device as characterized in claim 2 and wherein the casing is provided with cani surfaces arranged to permit limited rotation of the valve and upon further rotation of said valve, to operate to move the valve endvvise during such further rotation.

Ll. A device as characterized in claim 2 and vvhereinthe rotary valve member projects from the open end of the casing and is formed with a plurality of longitudinal slots to register successively with the inlet openings in the casing and said Casing is provided at its open end With inclined surfaces, means on the valve member to engage said inclined surfaces When said valve is rotated, said inlet openings in the casing, said slots in said valve, and said inclined surfaces being so arranged relatively as to provide a successive opening of the air in lets and a longitudinal movement of said valve With said inlets open.

5. In a device of the character described, the combination of a casing forming a main air passage therethrough With a mixing chamber adjacent one end and a series of longitudinal slots forming air inlets adjacent the opposite end, a rotary valve member fitting Within the open end of said casing and closing the same and provided with longitudinal slots to register with said slots in the casing upon. rotation of the valve, means for rotating said valve, means for moving said valve longitudinally during rotation, a block fitting Within the casing with one end adjacent the inner end of the valve` said block being formed with a Venturi pas-` sage therethrough opening into the mixing chamber and with longitudinal passages outside the venturi also opening into the mixing chamber and forminfr a by-pass for air, said valve having an end Wall to coSe the inlet ends of said by-pass passages and to open the same upon endivise movement of the valve, and means for introducing fuel into said Venturi passage.

In testimony whereof I aliX my signature.

EMIL A. NELSON. 

